Daniela Piergili Fioretti

Field effectiveness of pyrantel and failure of Parascaris equorum egg count reduction following ivermectin treatment in Italian horse farms

A study was carried out to assess the field efficacy of ivermectin (IVM) and pyrantel pamoate (PYR) against Parascaris equorum. Seventy-three foals (3-18 months old) from 5 stud farms, not treated with anthelmintics in the previous 10 weeks and with individual faecal egg counts (FEC) >200, were included in the study. For each stud farm, 5-7 foals were included in the IVM-treatment group (IVM 0.2%, 200 mcg/kg body weight) or in the PYR-treatment group (PYR 38%, 13.2mg/kg body weight) and 3 were untreated as controls. For each foal, FECs were carried out before treatment (Day 0) and on Days 7 and 21. An individually based estimation of efficacy was assessed by a bootstrap simulation applied to different previously suggested formulae to evaluate the percent reduction of faecal egg counts (FECR). Two thousand bootstrap resamples were constructed from individual FECRs and the parasite population was considered susceptible for FECs >or=90 and 95% confidence interval (C.I.) >or=95%, suspected resistant for FECRs comprised between 80 and 90% and 95% C.I. <95% and resistant when FECR <or=80 and 95% C.I. <or=90%. IVM treatment was effective in foals from 2 farms, was equivocal at both study times in 1 farm and ineffective in 2 farms, while PYR was fully effective on all farms. This data shows that P. equorum-resistant populations are present also in Italy and the phenomenon is spreading in horses throughout Europe.

Seroprevalence and Risk Factors for Toxoplasma gondii Infection on Finishing Swine Reared in the Umbria Region, Central Italy

Toxoplasma gondii is a worldwide zoonotic protozoan parasite and pork is considered the major meat source of Toxoplasma infection in humans. To determine the prevalence of infection of Toxoplasma gondii in pigs reared in the Umbria Region (Central Italy), blood samples of 960 pigs from 10 different farms (96 for each farm) were randomly collected and tested for antibodies (IgG) against T. gondii using an IFA assay. Sera were screened at 1/16 titrr and the endpoint titre was determined. Farm management questionnaires were completed and used to develop descriptive statistics on the tested farms as well as to determine measures of association for risk factors for the presence of T. gondii‐seropositive pigs. A total of 155 seropositive pigs (16.14%) were identified; within herds prevalence ranged from 8.33 to 25%. The statistical analysis identified all‐in‐all‐out housing and cleaning method as risk factors for Toxoplasma infection.

Diagnostic Value of Conjunctival Swab Sampling Associated with Nested PCR for Different Categories of Dogs Naturally Exposed to Leishmania infantum Infection

ABSTRACT The objective of the present study was to evaluate the diagnostic performance of a noninvasive assay, conjunctival swab (CS) nested-PCR (n-PCR), for diagnosing canine leishmaniasis (CanL) in different stages of infection in comparison to the performance of the indirect immunofluorescence antibody test (IFAT), lymph node microscopy, and buffy coat n-PCR. To this end, we performed a cross-sectional survey among 253 nonselected dogs in areas of endemicity in central Italy. We also performed a longitudinal study of CS n-PCR among 20 sick dogs undergoing antileishmanial treatment. In the first study, among the 72 animals that were positive by at least one test (28.45%), CS n-PCR showed the best relative performance (76.38%), with a high concordance in comparison to standard IFAT serology (κ = 0.75). The highest positivity rates using CS n-PCR were found in asymptomatic infected dogs (84.2%) and sick dogs (77.8%); however, the sensitivity of the assay was not associated with the presence of clinical signs. In the follow-up study on treated sick dogs, CS n-PCR was the most sensitive assay, with promising prognostic value for relapses. The univariate analysis of risk factors for CanL based on CS n-PCR findings showed a significant correlation with age (P = 0.012), breed size (P = 0.026), habitat (P = 4.9 × 10−4), and previous therapy (P = 0.014). Overall, the results indicated that CS n-PCR was the most sensitive assay of the less invasive diagnostic methods and could represent a good option for the early and simple diagnosis of CanL infection in asymptomatic animals and for monitoring relapses in drug-treated dogs.

Seroprevalence of Toxoplasma gondii in wild boars (Sus scrofa) from Central Italy

Wild and farmed game meat consumption has been highlighted as an emerging risk factor for Toxoplasma gondii infection in humans. In Central Italy wild boar is widely distributed and is also one of the most popular game species. The main goal of the present study was to estimate the seroprevalence of T. gondii antibodies through a serological survey conducted on 400 hunted wild boars (250 males and 150 females) during three subsequent hunting seasons (2009–2011), using an Immunofluorescence Antibody Assay. The animals were sorted by age, determined on the evaluation of the dental table; 101 were <1 year old, 175 from 1 to 3 years, and 124 > 3 years. Antibodies against T. gondii were detected in 56 (14%) serum samples with titers ranging from 40 to ≥160; a significant association (p < 0.05) was found between seropositivity and age, but not gender, hunting districts, or year of sampling.

Are macrocyclic lactones useful drugs for the treatment of Parascaris equorum infections in foals

A study was carried out to assess the field efficacy of moxidectin (MOX) against Parascaris equorum in foals. A total of 70 foals from 2 Italian thoroughbred (Farms 1 and 2) stud farms and one trotter stud farm (Farm 3), aged 3-5 months and with faecal egg counts (FEC) f>or=300 eggs per gram (EPG) were included in the study. On each farm, foals were divided into 2 groups (of 10, 8 and 10 foals, respectively) and treated with either moxidectin (MOX, 400 mcg/kg b.w.) or ivermectin (IVM, 200 mcg/kg b.w.) on day 0 and examined for faecal count reduction (FECR) on day 14. Five, 4 and 5 foals, respectively, were kept as untreated controls. An individually based estimation of efficacy was assessed by a bootstrap simulation to evaluate the percent reduction of FECRs. Two thousand bootstrap resamples were constructed from individual FECRs and the parasite population was considered susceptible for FECs>or=90% and 95% lower confidence limit (CL)>90%, suspected resistant for FECRs>or=90% and 95% LCL<90% and resistant when FECR<90% and 95% LCL<90%. On day 14, foals with FECRs categorized as resistant or suspected resistant were treated with pyrantel pamoate (PYR, 13.2mg/kg b.w.) and examined for FECR on days 28 and 35. On day 14, MOX and IVM treatments were ineffective in all foals from both thoroughbred farms, while MOX ad IVM were effective (FECRs>90%) in 7 and 5 trotter foals, respectively, and remained >90% until day 35. PYR treatment given on day 14 to remaining 8 foals (3 MOX-treated and 5 IVM-treated) was fully efficacious at faecal examinations carried out on days 28 and 35.

Occurrence of Borrelia lusitaniae infection in horses.

The aim of the study was to investigate Borrelia burgdorferi sensu lato (s.l.) infection in horses exposed to heavy tick infestations. Blood samples of 98 healthy horses from 5 stud farms were examined by SNAP(®) 4D× and PCR to detect antibodies against B. burgdorferi s.l. and Borrelia DNA, respectively. Ten samples (15.3%) were antibody positive and 5 samples (5.1%) were both antibody and PCR positive. Sequence analysis showed the highest homology with the B. lusitaniae genospecies. No differences were found between sexes and stud farms, while age was significantly related to seropositivity (p<0.05). Our data confirms the presence of B. lusitaniae infection in horses, previously not clearly demonstrated.

Pathological changes caused by Anoplocephala perfoliata in the mucosa/submucosa and in the enteric nervous system of equine ileocecal junction

In this study, pathological changes caused by Anoplocephala perfoliata in the ileocecal junction were investigated in 31 regularly slaughtered mixed-breed horses of both sexes. Our results showed a significant relationship between parasite burden and grading of histopathological lesions in the mucosa and submucosa. Hypertrophy of the circular muscle layer was found in infected horses. Moreover, enteric nervous system evaluation showed a significant injury of intestinal nervous elements in the horses with moderate to high parasitism expressed as an increase of degenerative-regressive changes in neuronal cells and a decrease in the number of myenteric ganglia and neuronal cells. These findings can help to clarify the pathogenesis of intestinal motility disorders associated with A. perfoliata infection in horses.

Long-term effect of toltrazuril on growth performances of dairy heifers and beef calves exposed to natural Eimeria zuernii and Eimeria bovis infections.

The long-term effects of a toltrazuril treatment against natural Eimeria bovis and/or Eimeria zuernii infections were investigated in comparison with diclazuril and untreated controls on two dairy (Italian Friesian breed) and two beef (Chianina breed) farms. At each trial site, 30 calves were allocated into three groups of 10 calves each: T (treated with toltrazuril), D (treated with diclazuril) and C (left untreated). For 40 weeks post-treatment, the calves were weighed and examined clinically and parasitologically. The oocyst counts as well as the number of scour days were significantly lower in the T group than in the D and C groups. Final bodyweights and body condition scores of the T group exceeded those of groups C and D. The results confirmed that toltrazuril was highly efficacious, safe and provided productive benefits in dairy and beef calves.

Toxoplasma gondii in small ruminants in Northern Italy – prevalence and risk factors

OBJECTIVE The aim of the survey was to evaluate Toxoplasma gondii seroprevalence in small ruminants and possible risk factors associated with the infection. MATERIALS AND METHODS Sera from 474 goats and 502 sheep reared on 42 farms in northern Italy were collected and tested for IgG antibodies to T. gondii by IFAT (indirect immunofluorescence antibody test). To identify risk factors, a binary logistic regression analysis of the variables was performed. An audit form about farm management was used. RESULTS Antibodies to T. gondii were found in 96.6% of goat farms and in 87.5% of sheep farms; 41.7% goats and 59.3% sheep resulted positive. Seroprevalence was significantly higher in sheep than in goats. Seroprevalence values were similar in goats from eastern and western areas, whereas goats from the southern area were at lower risk of infection. Saanen goats presented the lowest seroprevalence (30.7 %), whereas cross-breed exhibited the highest rate (48.7%). Goats from farms housing both sheep and goats had an infection risk 1.39 times higher than goats from farms that did not house sheep. Animals bred on intensive farms showed lower prevalence (22.1%) in comparison with those from extensive (45.6%) or semi-intensive farms (60%). Sampling area was one of the strongest predictors of T. gondii infection in sheep flocks. Transhumant flocks showed a higher risk of infection by T. gondii compared with semi-intensive farms (66.8% vs. 38.4%). CONCLUSIONS The highest T. gondii seroprevalence values were registered in transhumant flocks of sheep and in family businesses rearing goats. As these traditional activities represent an important resource for the conservation of the territory and its economy, management practices for a better control of the disease should be improved.

Molecular and serological detection of tick-borne pathogens in donkeys (Equus asinus) in Italy

Donkeys, owing to the frequent outdoor activity, are exposed to a high risk of infection with tick-borne pathogens. This work aimed to detect exposure to Theileria equi, Babesia caballi, Anaplasma phagocytophilum and Borrelia burgdorferi s.l. of donkeys reared in Central Italy. For this purpose 122 adult donkeys were selected within 11 herds and submitted to blood collection. IgG antibodies to T. equi, B. caballi, A. phagocytophilum and B. burgdorferi s.l. were detected by IFAT. Conventional PCRs targeting the genes MSP2 and the flagellin were used for the detection of A. phagocytophilum and B. burgdorferi s.l. respectively and a Real Time PCR Sybr Green was used to detect Babesia/Theileria spp…. The species identity was determined by amplicons sequencing. Forty eight (39.3%) and 58 (47.5%) animals tested positive for T. equi and B. caballi antibodies, respectively; nine animals (7.4%) were found positive for antibodies against A. phagocytophilum whereas negative results were obtained for B. burgdorferi s.l. Twenty-six (21.3%) animals showed antibodies for both T. equi and B. caballi. Twenty-three (18.8%) donkeys were positive to Babesia/Theileria spp. PCR assay. Out of 21 sequenced amplicons, 20 were identified as T. equi, belonging to three main groups designated A, B and D and one as B. caballi group A. Neither A. phagocytophilum nor B. burgdorferi PCR results were positive. The study showed a high exposure of donkeys to tick-borne pathogens and provides information on the genetic identity of the T. equi strains circulating in Central Italy.